Peculiarities of biochemical and morphological adaptation of siberian crabapple (Malus baccata L. Borkh) to the conditions of insufficient humidity on the boundary between forest zone and dry steppe

• Published in: Contemporary problems of ecology 2015-05, Vol.8 (3), p.344-350
• Main Authors: Rudikovskiy, A. V, Rudikovskaya, E. G, Dudareva, L. V, Potemkin, O. N
• Format: Article
• Language: English
• Subjects: abscisic acid; Adaptation; Biochemistry; Biomedical and Life Sciences; drying; dwarfing; Ecology; Forests; Growth rate; humidity; indole acetic acid; Indoleacetic acid; Leaves; Life Sciences; Malus baccata; Plant populations; shoots; Steppes; Stomata; Transpiration
• ISSN: 1995-4255; 1995-4263
• DOI: 10.1134/S1995425515030105

The peculiarities of adaptation of Siberian crabapple to moisture shortage on the boundary between forests and the dry steppe are studied. A significant decrease in the growth rate that eventually leads to dwarfing is discovered. In the course of such adaptation, there is a reduction in the photosynthetic surface of leaves and increase in the stomatal density on the remaining leaves. Meanwhile, the size of stomata decreases, which helps optimize the loss of water during transpiration. The decrease in the growth rate of Siberian crabapple shoots is revealed to be accompanied by a threefold decrease in the content of endogenous indoleacetic acid (IAA) in tips of dwarf Siberian crabapple (116 ± 13 ng/g of dry weight for the dwarf forms vs. 350 ± 39 ng/g of dry weight for the tall-growing forms). There is no significant difference in the content of ABA in tips of both forms studied (210 ± 18 and 213 ± 21 ng/g of dry weight for tall-growing and dwarf plants, respectively).